This invention relates to a new implementation of a stereoscopic shutter viewing device. All shutter-type stereoscopic viewing devices operate on the principle of separately blocking and unblocking the view from each eye. The blocking is done in such a manner that whenever one eye has an unobstructed view of an object being observed, the other eye's view is blocked.
A three-dimensional presentation of complex data structures can be obtained when a shutter-type viewer is used in synchronism with a display device which can alternately display and blank the images to be seen by each eye. Proper control over the rate at which each eye views the image of an object and correct horizontal displacement between the left and right eye images will result in a continuous three-dimensional representation of the object being viewed.
Electromechanical shutter-type viewing devices have been discussed in the prior art, and at least one such device is available commercially under the trade name "Lorgnette". Such devices perform their required function, but have certain disadvantages. The principle objection to these devices is the bulky design necessary to house the mechanical switching mechanisms for each eye. Other disadvantages are that a mechanical switching device will generally operate slower and have a shorter operational lifetime than an electronic device.
The liquid crystal stereoscopic viewer of this invention is an electronic shutter device as opposed to existing electro-mechanical devices. The switching action of each of the two liquid crystal lenses, one for each eye, is controlled by alternately applying and removing a voltage potential across the liquid crystal material for each lens. The resulting effect is that the entire lens assembly changes successively between transparent and opaque states, for first one lens assembly and then for the other.
As there is no requirement for a mechanical shutter mechanism in the liquid crystal viewer, the resulting liquid crystal viewer assembly is smaller and of lighter weight than existing electromechanical viewing devices. Head-mounted stereoscopic viewers employing liquid crystal lenses are completely practical due to this inherent small size and weight.